metonym vs metonymy

metonym

noun
  • A word that names an object from a single characteristic of it or of a closely related object; a word used in metonymy. 

  • A concept, idea, or word used to represent, typify, or stand in for a broader set of ideas. 

metonymy

noun
  • The use of a single characteristic or part of an object, concept or phenomenon to identify the entire object, concept, phenomenon or a related object. 

  • A metonym. 

How often have the words metonym and metonymy occurred in a corpus of books? (source: Google Ngram Viewer )